Please add me to the list for an Ultimate...have always regretted not getting one a while ago.
Thanks
Thanks
Harness building for those inclined (1 Viewer)
- Thread starter slcfj62
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FJ62 Headlight Harness Build
Hello all. I have just finished up assembling my version of the slcfj62 harness. For the fifth relay I have set one up to control a set of driving lights that I want to come on when my bright are on. I plan to put a 3-way switch with in the aux lights for further control. For the power wires to the headlights I went with 12ga wire and for the control wires I used 14ga. I realize that the 14ga is overkill but is what I had in stock. If there is anyone out there that has one of slcfj62 harness or has built their own I would like to see the wiring input on the bottom side of the RTMR. If any one out there wants to make their own iI have listed the ports for the RTMR on the relay point on the schematic. Hopefully in the near future I will be able to complete the harness and will post more pictures.
Hello all. I have just finished up assembling my version of the slcfj62 harness. For the fifth relay I have set one up to control a set of driving lights that I want to come on when my bright are on. I plan to put a 3-way switch with in the aux lights for further control. For the power wires to the headlights I went with 12ga wire and for the control wires I used 14ga. I realize that the 14ga is overkill but is what I had in stock. If there is anyone out there that has one of slcfj62 harness or has built their own I would like to see the wiring input on the bottom side of the RTMR. If any one out there wants to make their own iI have listed the ports for the RTMR on the relay point on the schematic. Hopefully in the near future I will be able to complete the harness and will post more pictures.
Hey Erik I know there are a bunch of us over on t4r.org that could really use the auxiliary fuse / relay panel you were making. Please put me down for one if and when you start making them again. I'd go with Option C as shown here https://forum.ih8mud.com/showpost.php?p=5240849&postcount=11
Thanks so much!
Thanks so much!
jwbc84 and slcfj62 (and anyone else who has done this),
Help me understand some basics. I have a hard time turning wiring schematics into mental reality.
There are 2 bundles of wires coming through my firewall - one on the driver's side and one on the passenger side. Both of those bundles appear to each contain wires that eventually terminate in plugs that attach to the back side of my headlight lamps. I understand how headlights work and that there are relays somewhere along these circuits, but I'm not sure where they are at the moment.
My question is: where does the upgraded harness plug in? Am I plugging it into the plugs that attach to the back side of my headlight lamps? If so, this would appear to be adding an additional set of relays to the existing system (?)
Or, am I connecting the new harness somewhere further upstream? Within the engine compartment? On the carpeted side of the firewall? What becomes of the existing relays once the new harness is in? Is there cutting/splicing involved?
I can picture the new harness from the diagram, I just can't picture where/how it fits.
Help me understand some basics. I have a hard time turning wiring schematics into mental reality.
There are 2 bundles of wires coming through my firewall - one on the driver's side and one on the passenger side. Both of those bundles appear to each contain wires that eventually terminate in plugs that attach to the back side of my headlight lamps. I understand how headlights work and that there are relays somewhere along these circuits, but I'm not sure where they are at the moment.
My question is: where does the upgraded harness plug in? Am I plugging it into the plugs that attach to the back side of my headlight lamps? If so, this would appear to be adding an additional set of relays to the existing system (?)
Or, am I connecting the new harness somewhere further upstream? Within the engine compartment? On the carpeted side of the firewall? What becomes of the existing relays once the new harness is in? Is there cutting/splicing involved?
I can picture the new harness from the diagram, I just can't picture where/how it fits.
gregnash
Anal Retentive Analyst
So from what I gather the new harness plugs into the passenger side headlamp plug, then splits from there to the passenger side lamp and drivers side lamp. I do not believe the extra relays add any resistance that would hinder the functioning of the lights (my understanding is they are basic on/off switches). What the harness is really doing is cleaning up the old, thin lines and expanding the lines to new, thicker lines that will allow more power to go through.
It has been a long time since I messed with electricity but if I remember correctly basically the size of the wire is what causes resistance to the power going through the line. The thicker the wire, the more power that is allowed through, thinner wire allows less. Now you do have to add the amount of power that is going through the lines and the distance that it is traveling into the equation. I am sure that this is a very dumbed down version and there is much more that goes into it but this is how I understand it.
It has been a long time since I messed with electricity but if I remember correctly basically the size of the wire is what causes resistance to the power going through the line. The thicker the wire, the more power that is allowed through, thinner wire allows less. Now you do have to add the amount of power that is going through the lines and the distance that it is traveling into the equation. I am sure that this is a very dumbed down version and there is much more that goes into it but this is how I understand it.
So if I understand Greg's explanation correctly: with this upgraded harness, the existing wiring will serve only to act upon an additional set of relays. The new relays will, in turn, direct illumination power that is being fed through new wiring.
In other words, existing wiring converts to switching function only, and the whole system gains a redundant relay set. Is that right?
In other words, existing wiring converts to switching function only, and the whole system gains a redundant relay set. Is that right?
gregnash
Anal Retentive Analyst
Yeah that is my basic understanding of it. Now if I could just understand the routing of the wires.
I've had a few questions as to how I built my harness so I thought I would share the information here. Hopefully it serves to aid somebody building something at home and expand their knowledge and/or confidence. Most of this information was gleaned from this site, and I personally extend my grateful appreciation for those who have shared. I have a highly modified franken-cruiser that I take pride in improving when I have the budget and band-aiding when I don't. I get copious amounts of joy in fixing or making something for exponentially less what I would have paid someone else for.
To build the same harnesses I did for my FJ62, you will need four relays. I use cheap ones from ebay because they are inexpensive and abundant. I think I have five in my spare parts bin although I have never needed to replace one. I'd find the relays that come with the sockets and have a reasonable gauge wire. Because this is a short run to the fuse block, 12ga or 10ga wire will work. I would not run 14ga wire for anything but the relay controls.
To adapt (and avoid cutting the OEM harness) I used a pair these Sealed Beam to H4 adapters that came with my H4 housings. I used the factory harness side of these to adapt the harness to the relays. You can find them much cheaper than $14.
I used four Hi Temp H4 connectors to adapt the output of the harness to the four headlights.
Post #33 has the relay set-up for the harness that you need to make. Remember that you need to make two of them, one for each side. Note that this diagram has an image of the connector that is as you are looking at the plug on the vehicle side (which is confusing because everything else has been back of the bulb view)
A pinout of the H4/9003 and the sealed beam connectors. This helps.
I did not buy special waterproof connectors as I don't do deep water crossings. I did put everything into wire looms and used plenty of good electrical tape. I soldered all of the splices and used relay sockets. If you want to take it a step further, you can get butyl tape from grainger.
Despite having 20 years of experience in electronics, I still like to spot check what the diagram says, and what actually exists. For instance, I connected 12V to the lo beam connector and ground to the common connector and verified that the light output of the sealed beam and H4 both had the appropriate cutoff in the light pattern. Then I knew that the diagram was correct.
Using two adapters allows you some flexibility. For instance, you could leave in the R/L separation, or you could set it up so that one adpater runs the inners, while the other runs the outers.
To build the same harnesses I did for my FJ62, you will need four relays. I use cheap ones from ebay because they are inexpensive and abundant. I think I have five in my spare parts bin although I have never needed to replace one. I'd find the relays that come with the sockets and have a reasonable gauge wire. Because this is a short run to the fuse block, 12ga or 10ga wire will work. I would not run 14ga wire for anything but the relay controls.
To adapt (and avoid cutting the OEM harness) I used a pair these Sealed Beam to H4 adapters that came with my H4 housings. I used the factory harness side of these to adapt the harness to the relays. You can find them much cheaper than $14.
I used four Hi Temp H4 connectors to adapt the output of the harness to the four headlights.
Post #33 has the relay set-up for the harness that you need to make. Remember that you need to make two of them, one for each side. Note that this diagram has an image of the connector that is as you are looking at the plug on the vehicle side (which is confusing because everything else has been back of the bulb view)
A pinout of the H4/9003 and the sealed beam connectors. This helps.
I did not buy special waterproof connectors as I don't do deep water crossings. I did put everything into wire looms and used plenty of good electrical tape. I soldered all of the splices and used relay sockets. If you want to take it a step further, you can get butyl tape from grainger.
Despite having 20 years of experience in electronics, I still like to spot check what the diagram says, and what actually exists. For instance, I connected 12V to the lo beam connector and ground to the common connector and verified that the light output of the sealed beam and H4 both had the appropriate cutoff in the light pattern. Then I knew that the diagram was correct.
Using two adapters allows you some flexibility. For instance, you could leave in the R/L separation, or you could set it up so that one adpater runs the inners, while the other runs the outers.
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Hi Eric,
I just heard back from Kevin Rowland... He said that you had suspended operations for a while, but might be accepting people on a wait list. I have a 1979 FJ40 with a "dimming" headlight issue. I think a relay would be the answer and yours got such good ratings, it would be worth waiting for (should you be interested). I would like a "basic" setup... please let me know your plans.
Thanks
Dale
multi-mediacorp@charter.net
I just heard back from Kevin Rowland... He said that you had suspended operations for a while, but might be accepting people on a wait list. I have a 1979 FJ40 with a "dimming" headlight issue. I think a relay would be the answer and yours got such good ratings, it would be worth waiting for (should you be interested). I would like a "basic" setup... please let me know your plans.
Thanks
Dale
multi-mediacorp@charter.net
thanks for those web sites Eric, have worked out which relays and module to get and all their connectors now only need to work out wires and their covers and the light connectors. lol been about 40 years since I worked a relay so I must have studied you drawings for 4 hours last night to get my brain working again, but should work out fine. Once again thanks
- Thread starter
- #32
A funny thing happened after I started this thread--I forgot to subscribe to it, so I basically haven't seen it since I started it. So, for anybody that expressed an interest in a headlight harness or auxiliary relay panel, please either PM me or email me (preferred) wiredwagon at comcast dot net.
Sent you a PM a little bit ago. Awesome Work!
Eric thanks for the harness work is impeccable. Thanks for the attention to detail and simplistic instructions.
...via IH8MUD app
...via IH8MUD app
Hi Eric, I sent you an email and a pm a couple of days ago hoping to get a harness and aux relay box
gregnash
Anal Retentive Analyst
Dont believe that Eric is actually making these anymore. That was kinda the purpose that he originally posted this thread was because he stopped taking orders for a while but people kept asking him for schematics. He did start doing them again but I wanna say in like 2016 he stopped again.
tmxmotorsports
SILVER Star
These are very much wanted here great idea i have installed one years ago the bussman box is very clean.
